1. Field of the Invention
The present invention relates to ferroelectric memory structures and more particularly to ferroelectric memory apparatus using transistor switches and ferroelectric capacitors as the storage elements.
2. Background Art
Attempts to incorporate ferroelectric technology into memory structures has been tried for more than thirty years. Ferroelectric memories usually take the form of a series connection of single transistor and a stack capacitor. The transistor is used to write as well as read the capacitor. The use of ferroelectric technology in memory structures that utilize a transistor as the switch and a ferroelectric capacitor as the storage medium usually suffer from read disturb problems. This occurs because reading normally requires a process in which stored bits can be flipped or, at least, disturbed from their state. Having to rewrite the disturbed bit is a severe penalty that is one of the reasons that continues to prevent adoption of ferroelectric technology in memories even though they offer the potential of high density, non-volatility and high speed.